A navigator is a device which provides guidance to a user as to how to travel from place to place. The guidance may include a map display, visual text instructions, or audible instructions.
In a wireless client-server (WCS) navigator, route searches and map generation are performed at a central location and transmitted to mobile units. The central server manages databases of geographical information and, in response to requests from the mobile clients, guidance in the form of maps, routes, and/or instructions are downloaded.
The engineering and business requirements of WCS navigation differ somewhat from those of standard standalone navigators. One major difference is that for WCS navigators, data transmission costs are a large part of the ongoing cost of operating the system. In order to economically provide WCS navigation, it is important to minimize the amount of data transmitted while still meeting customers' navigation needs.